Improved knitting machine equipped with two part needles

ABSTRACT

A knitting machine equipped with two-part needles each having a latchless hooked element and a relatively slidable loopcontrolling element having a loop retaining shoulder and a point for closing the hook. The hooked element has only one operating butt co-operable with cams of a single cam track. The two elements have abutments for contact with one another to effect movements of the elements together in both directions. Provision is made for lost motion between the elements. The stem of the loop-controlling element of each needle is formed for engagement with means in the machine for holding or restricting movements of the loop-controlling elements at required times.

United States Patent [191 Widdowson et a1.

[- 1 Aug. 13, 1974 1 IMPROVED KNITTING MACHINE EQUIPPED WITH TWO PARTNEEDLES Wildt Mellor Bromley Limited, Leicester, England Filed: Aug. 11,1972 Appl. No.: 279,794

Assignee:

Foreign Application Priority Data Aug. 28, 1971 Great Britain 40456/71References Cited UNlTED STATES PATENTS 5/1914 Pope et a1 66/115 12/1914Randall i 66/115 4/1917 Scott i 66/115 1/1923 La Montagne 66/1151,475,182 11/1923 Hanes ..66/12O 1,673,634 6/1928 Page 66/13 1,877,5039/1932 Gagne 66/123 FOREIGN PATENTS OR APPLICATIONS 1,023,553 11/1954Germany 66/115 Primary Examiner-Ronald Feldbaum Attorney, Agent, orFirmLarson, Taylor and Hinds 5 7 ABSTRACT A knitting machine equippedwith two-part needles each having a latchless hooked element and arelatively slidable loop-controlling element having a loop retainingshoulder and a point for closing the hook. The hooked element has onlyone operating butt cooperable with cams of a single cam track. The twoelements have abutments for contact with one another to effect movementsof the elements together in both directions. Provision is made for lostmotion between the elements. The stem of the loop-controlling element ofeach needle is formed for engagement with means in the machine forholding or restricting movements of the loop-controlling elements atrequired times.

15 Claims, 13 Drawing Figures PATENTED I 31974 8.828.582

' saw u 0F 4 Fla. 9.

IMPROVED KNITTING MACHINE EQUIPPED WITH TWO PART NEEDLES adjoining pointadapted to close the hook each time the needle is retracted to draw anew loop through a retained old loop and the latter is cast-off theneedle at a knocking-over point. Such a needle will be hereinafterreferred to as a two-part knitting machine needle of the form hereinreferred to.

Accordingly, the hook-closing point of the loopcontrolling element of atwo-part knitting machine needle of the form herein referred to takesthe place of the pivoted latch of a conventional needle of the latchtype. Hence, such a two-part needle overcomes the disadvantages of aconventional latch needle with its inherent latch weakness and itsliability to failure in modern high speed multi-feed machines.

Moreover, since the hooked element of a two-part needle of the formherein referred to is only called upon to make relatively smallrectilinear movements, in contradistinction to a conventional latchneedle to the latch of which requires to swing right open throughapproximately 180 before the advancing needle reaches its clearingposition, the cam lifting heights for operating a two-part needle of theaforesaid form can be reduced by as much as from 25 percent to percent.This, in turn, reduces cam lengths and makes possible an increase in thenumber of feeds in the machine. Added to this, two-part needles of thedescribed form impose less wear on cams, needle butts and the needle bedtricks because smoother forms of cam tracking are possible withshallower cam rises.

With a two-part needle of the herein referred to form in operation, thehooked element and the associated loop-controlling element in frontthereof are sometimes required to slide together and at other timesthere is relative sliding movement between the two. That is to say,whenever the hooked element is advanced from its fully retractedposition to its intermediate advanced, i.e., tucking position, it doesso relatively to the loopcontrolling element which is held stationary orsubstantially so. But when the hooked element is advanced beyond thetucking position, the loop-controlling element is also advanced to asmall extent so that the old loop becomes retained on the shoulder and.positioned around the point. However, as the hooked element commencesits subsequent retraction to draw a new loop through the retained oldloopon the point, the loop-controlling element is again held stationaryor substantially so until, in fact, the hook is covered and therebyclosed by the point. Therefore, both elements are retracted togethersufficiently far to enable the old loop to be cast-off the needle at theknocking-over position.

Heretofore, these various sliding movements of the said two elements intheir trick in the needle bed, both together and relatively, have beeneffected by cams of separate cam tracks which have respectively beenarranged to act upon two separate operating butts one on the stem of thehooked element and the other on the stem of the associatedloop-controlling element. Naturally, the provision of two operatingbutts on each twopart needle and of two corresponding needle-operatingcam tracks has complicated a knitting machine equipped with suchneedles.

The primary object of the present invention is to provide a generallyimproved two-part needle of the form herein referred to which is adaptedto be operated by cams in a single cam track.

Another object is to provide, in a knitting machine equipped with theimproved two-part needles, simple and effective means for exercisingcontrol over the yarn-controlling elements of those needles.

According to this invention, the hooked element only of the improvedneedle is furnished with an operating butt, this butt being co-operablewith cams of a single cam track for effecting the required rectilinearadvancing and retracting movements of the hooked element, the slidingmovements of the loop-controlling element together with the hookedelement in both directions being effected by mutual contact betweenabutments respectively provided on the two elements, there beingprovision for lost motion between the two elements to permit of therequired sliding movements of the hooked element relatively to theloop-controlling element, and the stem of the latter being formed forengagement with means of any suitable character in a knitting machine tohold or restrict movement of the loop-controlling element at requiredtimes.

The abutments on the two elements arranged to come into contact with oneanother whenever the loopcontrolling element is required to be advancedby and together with the hooked element may advantageously consist of arelevant edge of the aforesaid operating button the hooked element andthe opposed extremity of the tail portion of the stem of theloop-controlling element.

On the other hand, the abutments on the two elements arranged to comeinto contact with one another whenever the loop-controlling element isrequired to be retracted by and together with the hooked element, mayconveniently consist of a relevant edge of a frontal projection on thestem of the hooked element and an opposed shoulder on theloop-controlling element constituted by one end of a recess formed onthe back of the stem of the last mentioned element.

The aforementioned lost motion between the two elements is achieved bythe provision of the recess in the back of the loop-controlling elementand the extent of the lost motion is determined by the length of thisrecess.

Although the improved two-part needle of this invention is, as alreadydescribed, furnished with only one principal operating butt which is, ineffect, common to both of the elements of the needle, the latter may, ofcourse, be provided with any required number of additional butts, e.g.,for selection purposes and knitting variations. v

The improved needle, moreover, is applicable to circular knittingmachines, both plain and rib, as well as to flat bed knitting machinesof all appropriate types.

As to the means in a knitting machine for holding, i.e., restrictingrectilinear sliding movements of, the loop-controlling elements atrequired times, such means may take any appropriate one of variousforms.

For example, in the case where improved two-part needles of thisinvention are mounted in a needle cylinder yieldable and over-ridablelatching means comprising a spring retaining band which embraces thecylinder and is engageable in recesses in' the stems of theloop-controlling elements may be employed. Alternatively, theloop-controlling elements may themselves be made yieldable, e.g., by theprovision in their back edges of suitable reliefs, and be formed on thefront flat knitting machine, either a straight spring member,-

engageable in recesses in the stems of the loopcontrolling elements maybe provided, or a straight suitably grooved fixed bar may be arranged inassociation with the bed for co-operation with protuberances onyieldable loop-controlling elements.

But, in yet another possible arrangement, applicablemore especially to aflat needle bed or a needle dial (but also applicable to a needlecylinder), the loopcontrolling elements may be formed for engagementwith movement-restricting stops, abutments, plates, cam portions or thelike fitted in suitable positions to the cam plate, the dial cam-cap orthe cylinder cam box, as the case may be. The idea in this furtherarrangement is that, by virtue of the relative movement between theneedle bed and the cam plate the dial cam cap or the cylinder cam box,as the case may be, the loopcontrolling elements of the two-part needlesat the relevant times either strike, or'are struck by, the stops,abutments, plates, cam portions or the like and are thereby temporarilyheld, i.e., restricted in their sliding movements, and at all othertimes are clear of the restricting parts soas to be free for movementstogether with the associated hooked elements. But in this furtherarrangement, the provision of a retaining bar or ring is necessrary tohold the loop-containing elements in in their tricks in front of thehooked elements.

Yet again, the loop-controlling elements may, if desired, befrictionally held in their tricks and thereby restricted from movementuntil such times as they are forcibly moved against the frictionalinfluence by virtue of being contacted by projections or butts on thecorresponding hooked elements. For instance, the stem of eachloop-controlling element may be laterally bowed or crimped suchwise asto produce friction between it and the opposite side walls of its trick.In this variation, 21 flat retaining bar, or ring, according to the formof the needle bed employed, is provided to retain the loopcontrollingelements in the bed.

A still further possibility is for loop-controlling elements, retainedin the needle bed by a retaining bar or ring, to be prevented fromsliding movements in their tricks at appropriate times by a restrictorbar or ring which is cut away both at the places where the associatedhooked elements are advanced to clearing positions and also at the oldloop-knocking-over positions where the hooked elements and theloop-controlling elements are retracted together.

Where, as may be, the hooked element of the improved needle is formedwith a swell portion adjacent to the hook, this portion mayadvantageously be grooved for reception and guidance of theloopcontrolling element. But such a groove may not be essential in whichcase it can be eliminated.

In order that the invention may be more clearly understood and readilycarried into practical effect, specific constructional examples thereofwill now be described with reference to the accompanying drawings,wherein,

FIG. 1 is a vertical sectional view of a needle cylinder and its cambox, showing a two-part needle fully retracted, this needle functioningin conjunction with a yieldable and over-ridable latching meansincluding a simple spring retaining band,

FIGS. 2, 3 and 4 are three similar views but with the needle shown atrespectively different stages during a knitting cycle,

FIG. 5 is a detail vertical sectional view showing a modification,

FIG. 6 illustrates the single cam track for operating and controllingthe two-part needle illustrated in FIGS. 1 4,

FIG. 7 is a view similar to FIG. 1 illustrating an example of themodification in which the loop-controlling elements are yieldable forco-operation with a grooved ring,

FIG. 8 is another similar view depicting an arrangement wherein theloop-controlling elements are formed for engagement withmovement-restricting abutments or cams,

FIG. 9 illustrates a section of the cylinder cam system suitable forcontrolling two-part needles as depicted in FIG. 8,

FIG. 10 is a still further view similar to FIG. 1 showing a variation inwhich'the loop-controlling elements are frictionally held in theirtricks,

FIG. 11 comprises an edge view of one of such loopcontrolling elementsand also a fragmentary elevational view of the tricked face of a needlecylinder showing a frictionally held loop-controlling elementaccommodated in one of the tricks, and

FIG. 12 is a detail view hereinafter to be described,

FIG. 13 is a detailed view similar to FIG. 12 but showing the portionsin perspective view for greater clarity.

Referring to FIG. 1, the numeral 1 indicates a section of an annular cambox with a cam track 2, and 3 indicates a needle cylinder. The numerals4 and 6 respectively indicate the hooked element and the loopcontrollingelement of a two-part needle according to this invention. On the frontof the stem of the hooked element 4 is provided a rectangularly shapedprojection 7 arranged in an elongated recess 60 formed on the back ofthe stem of the loop-controlling element 6. The upper and lower ends ofthis recess define shoulders on the element 6. In conjunction with theloop-controlling elements 6 there are provided yieldable and overridablelatching means which include a spring retaining band 8 which completelyembraces the cylinder 3 and is cngageable in one or the other of tworecesses 6b and 60 formed in the front or outer edge of the stem of theloop-controlling element 6, there being a protuberance 6d on the stembetween those two recesses so as to define and separate the same. Therecess 6b in the stern of each loop-controlling element 6 nearest to abevelled point 13 of the latter is for holding the said elementstationary or substantially so whenever the corresponding hooked element4 is relatively advanced to its intermediate tucking position, whereasthe other recess 6c farthest from the point is for holding theloopcontrolling element 6 whenever the hooked element 4 commences itssubsequent retraction to draw a new loop and until the hook 4a is closedby the point 13.

The recess 60 farthest from the point 13 of the loopcontrolling element6 is just of a sufficient dimension, lengthwise of the said element, asto hold the latter stationary relatively to the hooked element 4whenever the spring retaining band 8 is engaged in this particularrecess. On the other hand, the recess 6b nearest to the point 13 iselongated somewhat and made of such length as to enable the two elements4 and 6 of the needle to be retracted together a variable distancedepending on the precise desired length of the new loop being drawn, inaccordance with the quality setting of the stitch cam.

In any event, the functioning of the yieldable latching means justdescribed is such that whenever the hooked element 4 is advanced beyondits tucking position and the two elements of the needle move together,the spring band 8 will be o,ver-ridden, i.e., acted upon and caused toyield by the protuberance 6d between the two recesses whereby it isforcibly displaced from the elongated recess 6b and thereupon permittedto spring into the companion short recess 60. Conversely, whenever thetwo elements 4 and 6 are retracted together, the spring retaining band 8will again be acted upon and caused to yield by the protuberance 6d sotha the band will be displaced from the short recess 60 farthest fromthe point 13 and permitted to spring into the elongated recess 6bnearest to the said point.

Immediately beneath its hook 4a the element 4 is formed with a swellwhich, as shown most clearly in FIG. 12, is grooves at 9 to receive andguide the upper portion of the element 6. e

In FIG. 1 th two-part needle has just drawn a new loop 5, the old loophaving been cast off the needle. The elements 4 and 6 have just beenretracted together, the band 8 is in the longer one 612 of the tworecesses 6b and 6c and the upper edge 11a of a single operating butt 11on the hooked element 4 is below and clear of an edge 10 at the lowerextremity of the element 6.

In FIG. 2 the hooked element 4 has been advanced, i.e., raised, to itsintermediate tucking height above the cylinder verge, theloop-controlling element 6 being meantime restrained from upwardmovement by engagement of the band 8 with the protuberance 6d at thelower end of the recess 611 until the tail edge 10 of the element 6 iscontacted by the upper edge 11a of the butt 1]. At this stage, moreover,the upper edge 70 of the projection 7 on the element 4 is in contactwith the shoulder at the upper end of the recess 6a.

In FIG. 3 the hooked element 4 has been fully advanced, with the oldloop 12 positioned over or around the point 13 and supported upon theold loop retaining shoulders rs of the loop-controlling element 6 and ayarn 14, fed by a suitable feeder or guide, being taken into the hook4a. The old loopretaining shoulder rs is more clearly shown in FIGS. 5and 12.

Referring to FIG. 4, it will be seen that the loopcontrolling element 6is held by the spring band 8 (at' this stage engaged in the recess 6b)while the hooked element 4 is being retracted with the yarn 14 in itshook 4a. It is to be noted that at this stage the hook is covered, andthus closed, by the point 13. The rectangular projection 7 on theelement 4 is now in contact with a shoulder 15 defined by the lower endof the recess 60 in the loop-controlling element 6, so that both of theelements 4 and 6 will be retracted, i.e., lowered, together during thedrawing of a new loop 12 of the yarn 14 through the loop 12.

FIG. 5 illustrates a variation in which a groove in the swellimmediately beneath the hook 4a of the hooked element 4 is eliminated.

As to the single cam track illustrated in FIG. 6, this incorporates aswing cam 16 which is adapted to be set in one of two positions, viz.,either the position shown to raise the hooked elements 4 to fullknitting or clear ing height, or a lower position to raise the hookedelements to tucking height only. Alternatively, solid fixed cams (notshown) for knitting or tucking may be employed. In another arrangement,conventional jack lifting cam such as 18 (for knitting, or tucking) maybe provided for use in conjunction with normal pattern selectiondevices.

Referring to FIG. 7, the back edge of the stem of each of theloop-controlling elements 6 is relieved at 6e to enable it to yieldradially inwards whenever a rounded lobe 19 on the front edge of thesaid stem is acted upon by a protuberant annular rib 20 on a sec tionalgrooved ring 21 which surrounds the needle cylinder 3 and is mounted ontop of the cam box 1. The ring 21 has formed in its annular face twosuperimposed movement-restricting grooves 22 and 23 separated by the rib20. The lobe 19 on each element 6 engages in one or the other of the twogrooves.

In the variation shown in FIGS. 8 and 9, the front edge of the stern ofeach element 6 is formed with a triangular-shaped butt 24 for contactwith either the lower upwardly bevelled edges (during advance of thehooked element 4) or the upper downwardly bevelled edges (duringretraction of the element 4) of movement-restricting abutments or camformations such as 25 provided on a sectional ring 26. This ring, likethe ring 21 in FIG. 7, surrounds the needle cylinder 3 and is mounted ontop ofthe cam box 1. Moreover, the ring 26, also like the ring 21,serves to hold the loopcontrolling elements 6 back against the frontedges of the hooked elements 4. As will be appreciated, both of theelements 4 and 6 of a two-part needle are permitted to move togetherwhenever they pass through gaps 27 (see FIG. 9) between the abutments orcam formations 25.

In FIG. 10 is shown, in side elevation, a loopcontrolling element 6which, as seen in FIG. 11 from the outside of the needle cylinder 3, islongitudinally bowed from end to end. Thus, when accommodated in itstrick 28, the opposite sides of each element 6 make efficient frictionalcontact with the respectively opposite side walls of the trick 28. Inthis way, the element 6 is frictionally held and can only be positivelymoved against the movement-restricting frictional influence by contactwith the hooked element 4 at appropriate stages of the cam-controlledraising and lowering movements thereof. In the FIG. 10 variation a ring26' is provided to hold the elements 6 back against the front edges ofthe companion elements 4.

FIGS. 12 and 13 shows more clearly than any of the other figures theswell 29 of the hooked element 4, which swell is grooved at 9 to receiveand guide the upper end portion, i.e., the suitably bevelled point 13,of the loop-controlling element6. FIGS. 12 and 13 also shows that thispoint 13 and the adjoining upper portion of the said element is reducedsomewhat in thickness at 30 to enable it to be slidably engaged withinthe groove 9. Alternatively, the upper region of the element 6 may be oftapered cross-section at 30 to cooperate with a vee groove in the swell29.

Weclaim:

1. A knitting machine including a tricked needle bed and, mounted intricks in said bed, two-part knitting needles each comprising (a) anindividually slidable and latchless hooked element having an open yarnreceiving and drawing hook and (b) an independently and relativelyslidable loop-controllingelement operable in front of the hooked elementand having an old loop retaining shoulder and an adjoining point adaptedto contact or cover the hook each time the needle is retracted to draw anew loop through a retained old loop and the latter is cast offtheneedle at a knocking-over point: wherein the improvement resides in theprovision on the hooked element of each two-part needle of only oneoperating butt which is co-operable with cams of a single cam track foreffecting required rectilinear advancing and retracting movements of thesaid hooked element; and in that the sliding movements of theloop-controlling element together with the hooked element of each needlein both directions are effected by mutual contact between abutments onthe two elements; provision being made for lost motion between the saidtwo elements to permit the required sliding movements of the hookedelement relatively to the loop-controlling element, saidloop-controlling element and a portion of the machine adjacent theloopcontrolling element constituting, respectively, first and secondcooperating parts, and including restricting means for restrictingrectilinear movement of the loopcontrolling element relative to themachine, said restricting means including at least two recesses, both ofwhich are on one'of said cooperating parts, said recesses separated by aprotuberance, and a projection on the other of said cooperating parts,said projection projecting into either of said recesses, said projectionarranged to override the protuberance to move to either of saidrecesses.

2. A knitting machine according to claim 1, wherein abutments on the twoelements of each twopart needle arranged to come into contact with oneanother whenever the loop-controlling element is required to be advancedby and together with the hooked element consists of an edge of theoperating button the hooked element and the opposed extremity of a tailportion of the stem of theloop-controlling element.

3. A knitting machine according to claim 1, wherein abutments on the twoelements of each two-part needle arranged to come into contact with oneanother whenever the loop-controlling element is required to beretracted by and together with the hooked element consists of a relevantedge of a frontal projection on the stem'of the hooked element and anopposed shoulder on the loop-controlling element constituted by an endof a recess formed in the back of the stem of the last mentionedelement.

4. A knitting machine according to claim 3, wherein the said recessformed in the back edge of the stem of the loop-controlling element ofeach two-part knitting needle provides lost motion between the twoelements of the needle, the extent of this lost motion being determinedby the length of said recess.

5. A knitting machine according to claim 1, wherein said restrictingmeans includes a yieldable and overridable member which yieldinglycontacts the needle bed and is engageable in recesses in the stems ofsaid loop-controlling elements.

6. A knitting machine according to claim 1, said restricting meansincluding the construction wherein the loop-controlling element of eachtwo-part knitting needle is made yieldable by providing a relief initsback edge and is formed on the front edge of its stem with aprojection in the form of a single lobe for engagement in either one orthe other of said recesses in the form of two grooves formed in a fixedcontrol component located adjacent to the needle bed.

7. A knitting machine according to claim 1, said restricting meansincluding the construction wherein the loop-controlling elements of thetwo-part knitting needles are formed for engagement withmovementrestricting formations on a restrictor component which serves tohold the said loop-controlling elements into their tricks in front ofthe hooked elements.

8. A knitting machine according to claim 5, wherein there are formed inthe front edge of the stem of the loop-controlling element of eachtwo-part knitting needle two recesses which are defined and separated byan intermediate protuberance on the stem, the recess nearest to thepoint of the loop-controlling element being adapted to co-operate withthe spring retaining member to hold the said element substantiallystationary whenever the correspondinghooked element is relativelyadvanced to an intermediate tucking position, whereas the other recessfarthest from the said point is for holding the loop-controlling elementwhenever the hooked element commences its subsequent retraction to drawa new loop and until the hook is contacted or covered by the point, thespring retaining member being acted upon and caused to yield by theprotuberance so that the member is displaced from the relevant recessand permitted to spring into the other recess whenever the two elementsare caused to move together in either of said advancing and retractingdirection.

9. A knitting machine according to claim 8, wherein the recess farthestfrom the point is of just sufficient dimension, lengthwise of theloop-controlling element, as to hold the latter stationary relatively tothe hooked element whenever the spring retaining member is engaged inthis particular recess, whereas the recess nearest to the point iselongated and of such length as to enable the two elements to beretracted together a variable distance depending on the desired lengthof the new loop being drawn.

10. A knitting machine according to claim 1, wherein the hooked elementof each two-part knitting needle is formed adjacent to its hook with aswell portion which is grooved for reception and guidance of theloopcontrolling element.

11. A knitting machine according to claim 10, wherein the point andtheadjoining upper portion of the loop-controlling element is reduced inthickness to enable it to be slidably engaged within the groove in theswell portion of the hooked element.

12. A knitting machine according to claim which is of the circular typeand wherein the spring retaining member is in the form of a bandembracing a tricked needle cylinder in which the two-part knittingneedles are mounted.

13. A knitting machine according to claim 6, which is of the circulartype and wherein the two-part knitting needles are mounted in a trickedneedle cylinder, the single lobe on the front edge of the stem of theloopcontrolling element of each needle being rounded and arranged to beacted upon by a protuberant annular rib on a sectional ring whichsurrounds the needle cylinder and has formed in its annular face twomovementrestricting grooves separated by the said rib and in one or theother of which the said lobe engages.

14. A knitting machine according to claim 1 which is of the circulartype and has a tricked needle cylinder wherein the two-part knittingneedles are mounted therefore.

15. A knitting machine including a tricked needle bed and, mounted intricks in said bed, two-part knitting needles each comprising (a) anindividually slidable and latchless hooked element having an open yarnreceiving and drawing hook and (b) an independently and relativelyslidable loop-controlling element operable in front of the hookedelement and having an old loop retaining shoulder and an adjoining pointadapted to contact or cover the hook each time the needle is retractedto draw a new loop through a retained old loop and the latter is castoff the needle and a knocking-over point: wherein the improvementresides in the provision on the hooked element of each two-part needleof only one operating butt which is co-operable with cams of a singlecam track for effecting required rectilinear advancing and retractingmovements of the said hooked element; and in that the sliding movementsof the loop-controlling element together with the hooked element of eachneedle in both directions are effected by mutual contact betweenabutments on the two elements; provision being made for lost motionbetween the said two elements to permit the required sliding movementsof the hooked element relatively to the loop-controlling element, andthe stem of the latter being formed for engagement with means in themachine for holding or restricting movement of the said loop-controllingelement at required times,

and wherein the front edge of the loop-controlling element of each suchneedle is formed with a triangular butt for contact with either thelower upwardly bevelled edges or the upper downwardly bevelled edges ofmovement-restricting abutments on a sectional ring surroundingthe saidneedle cylinder, this ring serving to hold the loop-controlling elementsback against the front edges of the hooked elements and both of theelements of each needle being permitted to move together whenever theypass through gaps between the said abutments.

1. A knitting machine including a tricked needle bed and, mounted intricks in said bed, two-part knitting needles each comprising (a) anindividually slidable and latchless hooked element having an open yarnreceiving and drawing hook and (b) an independently and relativelyslidable loop-controlling element operable in front of the hookedelement and having an old loop retaining shoulder and an adjoining pointadapted to contact or cover the hook each time the needle is retractedto draw a new loop through a retained old loop and the latter is castoff the needle at a knocking-over point: wherein the improvement residesin the provision on the hooked element of each two-part needle of onlyone operating butt which is co-operable with cams of a single cam trackfor effecting required rectilinear advancing and retracting movements ofthe said hooked element; and in that the sliding movements of theloop-controlling element together with the hooked element of each needlein both directions are effected by mutual contact between abutments onthe two elements; provision being made for lost motion between the saidtwo elements to permit the required sliding movements of the hookedelement relatively to the loop-controlling element, said loopcontrollingelement and a portion of the machine adjacent the loop-controllingelement constituting, respectively, first and second cooperating parts,and including restricting means for restricting rectilinear movement ofthe loop-contRolling element relative to the machine, said restrictingmeans including at least two recesses, both of which are on one of saidcooperating parts, said recesses separated by a protuberance, and aprojection on the other of said cooperating parts, said projectionprojecting into either of said recesses, said projection arranged tooverride the protuberance to move to either of said recesses.
 2. Aknitting machine according to claim 1, wherein abutments on the twoelements of each two-part needle arranged to come into contact with oneanother whenever the loop-controlling element is required to be advancedby and together with the hooked element consists of an edge of theoperating button the hooked element and the opposed extremity of a tailportion of the stem of the loop-controlling element.
 3. A knittingmachine according to claim 1, wherein abutments on the two elements ofeach two-part needle arranged to come into contact with one anotherwhenever the loop-controlling element is required to be retracted by andtogether with the hooked element consists of a relevant edge of afrontal projection on the stem of the hooked element and an opposedshoulder on the loop-controlling element constituted by an end of arecess formed in the back of the stem of the last mentioned element. 4.A knitting machine according to claim 3, wherein the said recess formedin the back edge of the stem of the loop-controlling element of eachtwo-part knitting needle provides lost motion between the two elementsof the needle, the extent of this lost motion being determined by thelength of said recess.
 5. A knitting machine according to claim 1,wherein said restricting means includes a yieldable and over-ridablemember which yieldingly contacts the needle bed and is engageable inrecesses in the stems of said loop-controlling elements.
 6. A knittingmachine according to claim 1, said restricting means including theconstruction wherein the loop-controlling element of each two-partknitting needle is made yieldable by providing a relief in its back edgeand is formed on the front edge of its stem with a projection in theform of a single lobe for engagement in either one or the other of saidrecesses in the form of two grooves formed in a fixed control componentlocated adjacent to the needle bed.
 7. A knitting machine according toclaim 1, said restricting means including the construction wherein theloop-controlling elements of the two-part knitting needles are formedfor engagement with movement-restricting formations on a restrictorcomponent which serves to hold the said loop-controlling elements intotheir tricks in front of the hooked elements.
 8. A knitting machineaccording to claim 5, wherein there are formed in the front edge of thestem of the loop-controlling element of each two-part knitting needletwo recesses which are defined and separated by an intermediateprotuberance on the stem, the recess nearest to the point of theloop-controlling element being adapted to co-operate with the springretaining member to hold the said element substantially stationarywhenever the corresponding hooked element is relatively advanced to anintermediate tucking position, whereas the other recess farthest fromthe said point is for holding the loop-controlling element whenever thehooked element commences its subsequent retraction to draw a new loopand until the hook is contacted or covered by the point, the springretaining member being acted upon and caused to yield by theprotuberance so that the member is displaced from the relevant recessand permitted to spring into the other recess whenever the two elementsare caused to move together in either of said advancing and retractingdirection.
 9. A knitting machine according to claim 8, wherein therecess farthest from the point is of just sufficient dimension,lengthwise of the loop-controlling element, as to hold the latterstationary relatively to the hooked element whenever the springretaining member is enGaged in this particular recess, whereas therecess nearest to the point is elongated and of such length as to enablethe two elements to be retracted together a variable distance dependingon the desired length of the new loop being drawn.
 10. A knittingmachine according to claim 1, wherein the hooked element of eachtwo-part knitting needle is formed adjacent to its hook with a swellportion which is grooved for reception and guidance of theloop-controlling element.
 11. A knitting machine according to claim 10,wherein the point and the adjoining upper portion of theloop-controlling element is reduced in thickness to enable it to beslidably engaged within the groove in the swell portion of the hookedelement.
 12. A knitting machine according to claim 5 which is of thecircular type and wherein the spring retaining member is in the form ofa band embracing a tricked needle cylinder in which the two-partknitting needles are mounted.
 13. A knitting machine according to claim6, which is of the circular type and wherein the two-part knittingneedles are mounted in a tricked needle cylinder, the single lobe on thefront edge of the stem of the loop-controlling element of each needlebeing rounded and arranged to be acted upon by a protuberant annular ribon a sectional ring which surrounds the needle cylinder and has formedin its annular face two movement-restricting grooves separated by thesaid rib and in one or the other of which the said lobe engages.
 14. Aknitting machine according to claim 1 which is of the circular type andhas a tricked needle cylinder wherein the two-part knitting needles aremounted therefore.
 15. A knitting machine including a tricked needle bedand, mounted in tricks in said bed, two-part knitting needles eachcomprising (a) an individually slidable and latchless hooked elementhaving an open yarn receiving and drawing hook and (b) an independentlyand relatively slidable loop-controlling element operable in front ofthe hooked element and having an old loop retaining shoulder and anadjoining point adapted to contact or cover the hook each time theneedle is retracted to draw a new loop through a retained old loop andthe latter is cast off the needle and a knocking-over point: wherein theimprovement resides in the provision on the hooked element of eachtwo-part needle of only one operating butt which is co-operable withcams of a single cam track for effecting required rectilinear advancingand retracting movements of the said hooked element; and in that thesliding movements of the loop-controlling element together with thehooked element of each needle in both directions are effected by mutualcontact between abutments on the two elements; provision being made forlost motion between the said two elements to permit the required slidingmovements of the hooked element relatively to the loop-controllingelement, and the stem of the latter being formed for engagement withmeans in the machine for holding or restricting movement of the saidloop-controlling element at required times, and wherein the front edgeof the loop-controlling element of each such needle is formed with atriangular butt for contact with either the lower upwardly bevellededges or the upper downwardly bevelled edges of movement-restrictingabutments on a sectional ring surrounding the said needle cylinder, thisring serving to hold the loop-controlling elements back against thefront edges of the hooked elements and both of the elements of eachneedle being permitted to move together whenever they pass through gapsbetween the said abutments.